Re: [BackupPC-users] Tuning for disk contention

2009-09-07 Thread Tino Schwarze
On Sat, Sep 05, 2009 at 06:52:35PM -0600, dan wrote: [...] > You make a lot more sence here, but I think you overestimate CPU usage. > backuppc is so IO bound that after your get a 2Ghz+ Dual core and 2GB RAM > you can pretty much blame your disks for slow performance. I have a dual > core 2Ghz

Re: [BackupPC-users] Tuning for disk contention

2009-09-06 Thread higuita
Hi On Sat, 5 Sep 2009 18:52:35 -0600, dan wrote: > >the "perfect" max load should be the number of cpus you have, > >so a quad-core server can sustain a load of 4 without any > >problem... after that number, the higher the load, the higher > >will be the performanc

Re: [BackupPC-users] Tuning for disk contention

2009-09-05 Thread dan
>the "perfect" max load should be the number of cpus you have, >so a quad-core server can sustain a load of 4 without any >problem... after that number, the higher the load, the higher >will be the performance lost > > I dont agree here at all. backuppc is not gener

Re: [BackupPC-users] Tuning for disk contention

2009-09-05 Thread dan
On Fri, Sep 4, 2009 at 4:05 PM, Michael Stowe wrote: > > It's an awfully good question, but there probably isn't a single right > answer. My server is a quad-cpu beast on a gigabit network, but I settled > on two backups at a time after measuring degradation (first back up one at > a time, then t

Re: [BackupPC-users] Tuning for disk contention

2009-09-04 Thread higuita
Hi On Fri, 4 Sep 2009 14:39:22 -0700, James Ward wrote: > What's a good IO/WAIT average to shoot for? Load average? Other > things I might not be thinking of? the "perfect" max load should be the number of cpus you have, so a quad-core server can sustain a load of 4 without a

Re: [BackupPC-users] Tuning for disk contention

2009-09-04 Thread Michael Stowe
It's an awfully good question, but there probably isn't a single right answer. My server is a quad-cpu beast on a gigabit network, but I settled on two backups at a time after measuring degradation (first back up one at a time, then two, then three...) Then again, neither my file system nor serv

[BackupPC-users] Tuning for disk contention

2009-09-04 Thread James Ward
The discussion over the various BackupPC scenarios got me to thinking. My server IS disk bound. All the servers it backs up on on at least a 100M network link in the same room and some on 1G. With the default settings (4 simultaneous backups), the system is sitting right now at load aver